/* -*- c -*- ------------------------------------------------------------- *
 *
 *   Copyright 2004 Murali Krishnan Ganapathy - All Rights Reserved
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
 *   Bostom MA 02111-1307, USA; either version 2 of the License, or
 *   (at your option) any later version; incorporated herein by reference.
 *
 * ----------------------------------------------------------------------- */

/* This program can be compiled for DOS with the OpenWatcom compiler
 * (http://www.openwatcom.org/):
 *
 * wcl -3 -osx -mt getargs.c
 */

#include "biosio.h"
#include "string.h"
#include "menu.h"

// Structures

// Declare a menusystem here
static t_menusystem menusystem;

/* Basic Menu routines */

void drawbox(char top, char left, char bot, char right,char attr, char page)
{
    char x;
    
    // Top border
    gotoxy(top,left,page);
    cprint(TOPLEFT,attr,1,page);
    gotoxy(top,left+1,page);
    cprint(TOP,attr,right-left,page);
    gotoxy(top,right,page);
    cprint(TOPRIGHT,attr,1,page);
    // Bottom border
    gotoxy(bot,left,page);
    cprint(BOTLEFT,attr,1,page);
    gotoxy(bot,left+1,page);
    cprint(BOT,attr,right-left,page);
    gotoxy(bot,right,page);
    cprint(BOTRIGHT,attr,1,page);
    // Left & right borders
    for (x=top+1; x < bot; x++)
    {
        gotoxy(x,left,page);
        cprint(LEFT,attr,1,page);
        gotoxy(x,right,page);
        cprint(RIGHT,attr,1,page);
    }
}

void printmenu(t_menu * menu, int curr, char top, char left)
{
    int x;
    int numitems,menuwidth;
    t_menusystem *ms;
    char attr;

    ms = & menusystem;
    numitems = menu->numitems;
    menuwidth = menu->menuwidth+2;
    clearwindow(top,left-1,top+numitems+1,left+menuwidth+1,ms->menupage,ms->fillchar,ms->shadowattr);
    drawbox(top-1,left-2,top+numitems,left+menuwidth,ms->normalattr,ms->menupage);
    // Menu title
    x = (menuwidth - strlen(menu->title) - 1) >> 1;
    gotoxy(top-1,left+x,ms->menupage);
    csprint(menu->title);
    for (x=0; x < numitems; x++)
    {
        gotoxy(top+x,left-1,ms->menupage);
        if (menu->items[x].action == OPT_INACTIVE)
        {
            attr = (x==curr? ms->revinactattr : ms->inactattr);
        } else {
            attr = (x==curr ? ms->reverseattr : ms->normalattr);
        }
        cprint(ms->spacechar,attr,menuwidth+1,ms->menupage);        
        gotoxy(top+x,left,ms->menupage);
        csprint(menu->items[x].item);
        gotoxy(top+x,left+menuwidth-1,ms->menupage); // Last char if any
        switch (menu->items[x].action)
        {
           case OPT_SUBMENU:
                cprint(SUBMENUCHAR,attr,1,ms->menupage);
                break;
           case OPT_CHECKBOX:
                cprint( (menu->items[x].itemdata.checked ? CHECKED : UNCHECKED),attr,1,ms->menupage);
                break;
        }
    }
    if (menusystem.handler) menusystem.handler(&menusystem,menu->items+curr);
}

void cleanupmenu(t_menu *menu, char top,char left)
{
    t_menusystem *ms = &menusystem;
    clearwindow(top,left-1,top+menu->numitems+1,left+menu->menuwidth+3,ms->menupage,ms->fillchar,ms->fillattr); // Clear the shadow
    clearwindow(top-1,left-2,top+menu->numitems,left+menu->menuwidth+2,ms->menupage,ms->fillchar,ms->fillattr); // clear the main window
}

/* Handle one menu */
t_menuitem * getmenuoption( t_menu *menu, char top, char left, char startopt)
// Return item chosen or NULL if ESC was hit.
{
    int curr;
    char asc,scan;
    char numitems;
    t_menusystem *ms;
    t_menuitem *ci; // Current item
    
    ms = & menusystem;
    numitems = menu->numitems;
    // Setup status line
    gotoxy(ms->minrow+ms->statline,ms->mincol,ms->menupage);
    cprint(ms->spacechar,ms->reverseattr,ms->numcols,ms->menupage);

    // Initialise current menu item    
    curr = startopt;
    gotoxy(ms->minrow+ms->statline,ms->mincol,ms->menupage);
    cprint(ms->spacechar,ms->statusattr,ms->numcols,1);
    gotoxy(ms->minrow+ms->statline,ms->mincol,ms->menupage);
    csprint(menu->items[curr].status);
    while (1) // Forever
    {
        printmenu(menu,curr,top,left);
        ci = &(menu->items[curr]);
        asc = inputc(&scan);
        switch (scan)
        {
            case HOMEKEY:
                  curr = 0;
                  break;
            case ENDKEY:
                  curr = numitems -1;
                  break;
            case PAGEDN:
                  curr += 5;
                  break; 
            case PAGEUP:
                  curr -= 5;
                  break; 
            case UPARROW:
                  curr --;
                  break;
            case DNARROW:
                  curr++;
                  break;
            case LTARROW:
            case ESCAPE:
                  return NULL;
                  break;
            case ENTERA:
            case RTARROW:
            case ENTERB:
                  if (ci->action == OPT_INACTIVE) break;
                  if (ci->action == OPT_CHECKBOX) break;
                  if (ci->action == OPT_EXITMENU) return NULL; // As if we hit Esc
                  return ci;
                  break;
            case SPACEKEY:
                  if (ci->action != OPT_CHECKBOX) break;
                  ci->itemdata.checked = !ci->itemdata.checked;
                  // Call handler to see it anything needs to be done
                  if (ci->handler != NULL) ci->handler(&menusystem,ci); 
                  break;
        }
        // Adjust within range
        if (curr < 0) curr=0;
        if (curr >= numitems) curr = numitems -1;
        // Update status line
        gotoxy(ms->minrow+ms->statline,ms->mincol,ms->menupage);
        cprint(ms->spacechar,ms->statusattr,ms->numcols,ms->menupage);
        csprint(menu->items[curr].status);
    }
    return NULL; // Should never come here
}

/* Handle the entire system of menu's. */
t_menuitem * runmenusystem(char top, char left, int currmenu)
/*
 * currmenu
 *    Which menu should be currently displayed
 * top,left
 *    What is the position of the top,left corner of the menu
 *
 * Return Value:
 *    Returns a pointer to the final item chosen, or NULL if nothing chosen.
 */
{
    t_menu *cmenu;
    t_menusystem *ms = &menusystem;
    t_menuitem *opt,*choice;
    int numitems;
    char startopt;

    startopt = 0;
startover:
    cmenu = (menusystem.menus+currmenu);
    numitems = menusystem.menus[currmenu].numitems;
    opt = getmenuoption(cmenu,top,left,startopt);
    if (opt == NULL)
    {
        // User hit Esc
        cleanupmenu(cmenu,top,left);
        return NULL;
    }
    if (opt->action != OPT_SUBMENU) // We are done with the menu system
    {
        cleanupmenu(cmenu,top,left);
        return opt; // parent cleanup other menus
    }
    if (opt->itemdata.submenunum >= menusystem.nummenus) // This is Bad....
    {
        gotoxy(12,12,ms->menupage); // Middle of screen
        csprint("Invalid submenu requested. Ask administrator to correct this.");
        cleanupmenu(cmenu,top,left);
        return NULL; // Pretend user hit esc
    }
    // Call recursively for submenu
    // Position the submenu below the current item,
    // covering half the current window (horizontally)
    choice = runmenusystem(top+opt->index+2, left+3+(cmenu->menuwidth >> 1), opt->itemdata.submenunum);
    if (choice==NULL) // User hit Esc in submenu
    {
       // Startover
       startopt = opt->index;
       goto startover;
    }
    else
    {
        cleanupmenu(cmenu,top,left);
        return choice;
    }
}

/* User Callable functions */

t_menuitem * showmenus(char startmenu)
{
    t_menuitem *rv;
    t_menusystem *ms;
    char oldpage,tpos;

    ms = & menusystem;
    // Setup screen for menusystem
    oldpage = getdisppage();
    setdisppage(ms->menupage);
    cls();
    //clearwindow(0,0,getnumrows()-1,getnumcols()-1,ms->menupage,' ',0x07);
    clearwindow(ms->minrow,ms->mincol,ms->maxrow,ms->maxcol,ms->menupage,ms->fillchar,ms->fillattr);
    tpos = (ms->numcols - strlen(menusystem.title) - 1) >> 1; // To center it on line    
    gotoxy(ms->minrow,ms->mincol,ms->menupage);
    cprint(ms->tfillchar,ms->titleattr,ms->numcols,ms->menupage);
    gotoxy(ms->minrow,ms->mincol+tpos,ms->menupage);
    csprint(menusystem.title);
    
    cursoroff(); // Doesn't seem to work?

    // Go
    rv = runmenusystem(ms->minrow+MENUROW, ms->mincol+MENUCOL, startmenu);

    // Hide the garbage we left on the screen
    cursoron();
    if (oldpage == ms->menupage) cls(); else setdisppage(oldpage);

    // Return user choice
    return rv;
}

void init_menusystem(const char *title)
{
    menusystem.nummenus = 0;
    if (title == NULL)
        strcpy(menusystem.title,TITLESTR);
    else strcpy(menusystem.title,title);

    menusystem.normalattr = NORMALATTR; 
    menusystem.reverseattr= REVERSEATTR;
    menusystem.inactattr = INACTATTR;
    menusystem.revinactattr = REVINACTATTR;

    menusystem.statusattr = STATUSATTR;
    menusystem.statline = STATLINE;
    menusystem.tfillchar= TFILLCHAR;
    menusystem.titleattr= TITLEATTR;
    
    menusystem.fillchar = FILLCHAR;
    menusystem.fillattr = FILLATTR;
    menusystem.spacechar= SPACECHAR;
    menusystem.shadowattr = SHADOWATTR;

    menusystem.menupage = MENUPAGE; // Usually no need to change this at all
    menusystem.handler = NULL; // No handler function

    // Figure out the size of the screen we are in now.
    // By default we use the whole screen for our menu
    menusystem.minrow = menusystem.mincol = 0;
    menusystem.numcols = getnumcols();
    menusystem.numrows = getnumrows();
    menusystem.maxcol = menusystem.numcols - 1;
    menusystem.maxrow = menusystem.numrows - 1;
}

void set_normal_attr(char normal, char selected, char inactivenormal, char inactiveselected)
{
    if (normal != 0xFF)           menusystem.normalattr   = normal;
    if (selected != 0xFF)         menusystem.reverseattr  = selected;
    if (inactivenormal != 0xFF)   menusystem.inactattr    = inactivenormal;
    if (inactiveselected != 0xFF) menusystem.revinactattr = inactiveselected;
}

void set_status_info(char statusattr, char statline)
{
    if (statusattr != 0xFF) menusystem.statusattr = statusattr;
    // statline is relative to minrow
    if (statline >= menusystem.numrows) statline = menusystem.numrows - 1;
    menusystem.statline = statline; // relative to ms->minrow, 0 based
}

void set_title_info(char tfillchar, char titleattr)
{
    if (tfillchar  != 0xFF) menusystem.tfillchar  = tfillchar;
    if (titleattr  != 0xFF) menusystem.titleattr  = titleattr;
}

void set_misc_info(char fillchar, char fillattr,char spacechar, char shadowattr)
{
    if (fillchar  != 0xFF) menusystem.fillchar  = fillchar;
    if (fillattr  != 0xFF) menusystem.fillattr  = fillattr;
    if (spacechar != 0xFF) menusystem.spacechar = spacechar;
    if (shadowattr!= 0xFF) menusystem.shadowattr= shadowattr;
}

void set_window_size(char top, char left, char bot, char right) // Set the window which menusystem should use
{
    t_menusystem *ms;
    
    char nr,nc;
    if ((top > bot) || (left > right)) return; // Sorry no change will happen here
    nr = getnumrows();
    nc = getnumcols();
    if (bot >= nr) bot = nr-1;
    if (right >= nc) right = nc-1;
    ms = &menusystem;
    ms->minrow = top;
    ms->mincol = left;
    ms->maxrow = bot;
    ms->maxcol = right;
    ms->numcols = right - left + 1;
    ms->numrows = bot - top + 1;
    if (ms->statline >= ms->numrows) ms->statline = ms->numrows - 1; // Clip statline if need be
}

void reg_handler( t_menusystem_handler handler)
{
    menusystem.handler = handler;
}

void unreg_handler()
{
    menusystem.handler = NULL;
}

char add_menu(const char *title) // Create a new menu and return its position
{
   char num = menusystem.nummenus;
   t_menu *m;

   if (num >= MAXMENUS) return -1;
   m = &(menusystem.menus[num]);
   m->numitems = 0;
   if (title)
   {
       if (strlen(title) > MENULEN - 2)
             strcpy(m->title," TITLE TOO LONG ");
       else strcpy(m->title,title);
   }
   else strcpy(m->title,"");
   m ->menuwidth = strlen(m->title);
   menusystem.nummenus += 1;
   return menusystem.nummenus - 1;
}


t_menuitem * add_item(const char *item, const char *status, t_action action, const char *data, char itemdata) // Add item to the "current" menu
{
    t_menuitem *mi;
    t_menu *m;

    m = &(menusystem.menus[menusystem.nummenus-1]);
    mi = &(m->items[m->numitems]);
    mi->handler = NULL; // No handler
    if (item) {
      if (strlen(item) > MENULEN - 2) {
        strcpy(mi->item,"ITEM TOO LONG");
      } else {
        strcpy(mi->item,item);
        if (strlen(item) > m->menuwidth) m->menuwidth = strlen(item);
      }
    } else strcpy(mi->item,"");

    if (status) {
      if (strlen(status) > STATLEN - 2) {
          strcpy(mi->status,"STATUS STRING TOO LONG");
      } else {
      strcpy(mi->status,status);
      }
    } else strcpy(mi->status,"");
    
    mi->action = action;

    if (data) {
      if (strlen(data) > ACTIONLEN - 2) {
          strcpy(mi->data,"ACTION STRING LONG");
      } else {
         strcpy(mi->data,data); // This is only null terminated
      }
    } else strcpy(mi->data,"");

    switch (action)
    {
        case OPT_SUBMENU:
            mi->itemdata.submenunum = itemdata;
            break;
        case OPT_CHECKBOX:
            mi->itemdata.checked = itemdata;
            break;
        case OPT_RADIOBTN:
            mi->itemdata.choice = itemdata;
            break;
    }
    mi->index = m->numitems++;
    mi->parindex = menusystem.nummenus-1;
    return mi;
}